SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60eddb99df1512d46c445707783379ff9328e14d077ec59753e970c212b68221' 
  AND token = 'jkY4lQ5qVkeBJECEZFpXSW2YAYf1HB1O/IUson/8GGc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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