SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '71059a544d88723a0e153346db3f9a2dada1df898806be8a347dcd6857a340a1' 
  AND token = 'CNqUg2wJWjx3/+eixKhHyIJVO9OMUiQ6jzoNsioXsBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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