SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b085ae4d7bfa317adf8a4d4347799d61a7dedaf451dcbd10af8456265610807c' 
  AND token = 'ttF7VgSKNJpb/JDKYFgZ31PuhfqaWO8/mr07QnPXYUI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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