SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0414c23f5aa0370e0623fdf187cd26680c52a378fc3741f31601b8bdc43219a' 
  AND token = 'QlbdfGyxQVB0xovxaqGDumPTLsId15f/Zr5j3HOs3zg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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