SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f7a06f599df8bec20e26104342a7cbb0ec288668ec8b3a1d22a9b1c92056705' 
  AND token = 'OtxJpcJwQKxui9IBn+I45KLMG8u3+40i71yP4kvc4XY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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