SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1d9a7c90cd0cb147b526bbcdfc33f603259511b4e4b67150bb5aa4b4f3e8bf8' 
  AND token = '1+fko1v9Q8t+LHS8VwnrJ43ELROrRLLNSJr66CsBCCs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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