SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8720a966e9254f99f854a22987a63e8be7b119ce0eb06deb3357f0a241b9bbe8' 
  AND token = '6tNacqATV+69QBcIHFTDkBM6w4Qb0bwsWAtanTMzQJA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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