SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0baca7c48fed77e7a1cdb298f552f530779be3854cb91e6940862a90583e546f' 
  AND token = 'b1J57+RCi40R+kNGhV21Omy/0ulvQpgU8K+pE9YHnMs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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