SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82a09df7272dc4d20f3d60bcd27c797bd6a2d2288aa6a47606ee9eecb0302fa5' 
  AND token = 'c3NvwEAz/ZeXw16trqkYf7Koz7v3OURCqWMiE/QByJc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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