SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '86a2295426c67701f6ab4260d73dfcc3f0fd0da5d3291d6e1e59ec373a26715f' 
  AND token = 'hMaThX0SynG0kasqW0cB/TPLrIKHGGPGmn/fPRFzOEk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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