SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '75ef3aaf7e1e9e1fc25167283d2fe4f5f9d1e7fcf7c0fb83e0e99e5da55138d4' 
  AND token = 'K+ob9lOCztQCSovuzru5jJo9rHm5Tc7RIEmkg/sL0qQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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