SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09df0d2a1cfe3cf0d4ac98428539d530b31bb5ef5832f2bead4765f20bcfe2fa' 
  AND token = 'ncwyQoCmPwuGzU7jRHayYJ1+cCwRatVAtw2N+2SHJiw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}