SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2f2bf7c3dd9f50e49164ff2998d42ae7d0b18e964adf9060464ef24902bf54b' 
  AND token = 'r1Kr7ohzUrXX9SjFfX3/YEr5bcZP58qkQdZMBmK3474=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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