SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '179600913f74f37fcb72e18ae95b871e6eb7c1630eb2c12004d719b899eca0b7' 
  AND token = '20xH9agtU6LGlsen0OdX1jSackTo76E+eEzdM4xiU8c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}