SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a545469321c30f3bc8caa5ea8cca9d53033d0702744cf520b03fed2a66957632' 
  AND token = 'NbfTjCIaBKWzrk5qEvv6b+vxZPZm/Gur6vUAis39Lz8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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